The present invention relates to a snap hinge for supporting closure plate-like or sheet-like elements, i.e. a hinge which is adapted to produce the snap closure and opening of doors and leaves, particularly in pieces of furniture, in caravan cabinets, in bins and in applications in general in which in order to pass from the open position to the closed position the sheet-like elements rotate about a substantially horizontal or optionally inclined hinge axis.
Hinges for pieces of furniture and the like are known which have a twin articulated quadrilateral and an enclosed spring which is optionally provided with a monolithic pusher lever, as in Italian patent no. 1,269,279 filed on Dec. 16, 1994 in the name of the same Applicant, producing snap opening and closure over an extent approximately equal to a right angle.
These hinges are not free from drawbacks, including the fact that they do not allow stable opening and closure and do not support the door sufficiently when it moves from the vertical position to a horizontal position in which the weight of the door itself acts particularly intensely on the hinges.
Accordingly, one obtains a smaller-than-expected degree of opening and/or an excessively weak closure, to the point of causing, for example in the case of application to caravans, accidental opening of the cabinet door on bends, causing the consequent escape of the contents of the cabinet.
Hinges adapted for recessed mounting, of the type with an articulated quadrilateral and a spring, are also known; they are applied so that one of the base plates is fixed in a recess formed within the thickness of the door so as to slightly increase the movement arm.
However, even these hinges do not ensure good stability of the doors, require molds or machining in order to obtain said recess, leading to a considerable production cost increase, and tend to make the door slam violently against the piece of furniture or cabinet during closure.
The aim of the present invention is to eliminate the above-described drawbacks of conventional hinges by providing a snap hinge for supporting closure sheet-like elements which allows to stably support the sheet-like element between the vertical position and the horizontal position, to provide stable closure and opening, to support very intense loads, to prevent the door from violently slamming against the piece of furniture or cabinet during closure, and to perform simple and straightforward assembly without having to form recesses and without resorting to molded doors provided with a recess.
Within the scope of this technical aim, an object of the present invention is to achieve the above-cited aim with a structure which is simple, relatively easy to provide in practice, safe in use, effective in operation and relatively low in cost.
This aim, object and others are both achieved by the present snap hinge for supporting closure sheet-like elements, comprising a first articulated quadrilateral and a second articulated quadrilateral which have a first lever and a second lever in common, characterized in that it is provided with at least two elastic means in parallel.